The present disclosure relates to cover or tarping systems for trailers, containers and trucks, and in particular to side roll tarping systems in which the cover is rolled or unrolled from one side of the trailer/container body to the other.
As shown in FIG. 1, a cover system 20 is mounted to a trailer, dump body or truck box 24. The top 25 of the body 24 is open for top-loading of materials, such as grain, refuse and the like, into the interior of the body. The cover system 20 is configured to cover the open top of the body to protect and contain the materials during transport. The cover system includes a roll-up tarp 28 that is rolled onto a bar 29 that is part of a deployment system 30. The deployment system 30 shown in FIG. 1 is a manual crank system, but it is understood that other types of manual and powered deployment systems may be used to roll or unroll the tarp to thereby extend or retract the cover relative to the top 25 of the body 24.
In some applications the cover or tarp may extend flat across the top of the body. However, in many applications, such as for hauling heaped loads, it is desirable for the cover to have a curvature or form an arc over the body. The cover system 20 thus includes a number of curved bows 31 that are mounted to a side rail 27a on one side of the body 24 by a pivot mount 34. The bows can thus pivot from a position extending across the top 24, as shown in FIG. 1, to a retracted position adjacent side rail 27a, as shown in FIG. 3. In the deployed position, the free ends of the bows can be held in position by an engaging element 36 at the opposite side rail 27a, which may be in the form of a collar configured to receive a post extending from the end of the bow. Other forms of engagement between the free ends of the bows 31 and the side rail 27b are contemplated.
When the cover 28 is retracted, the bows 31 can also be retracted to provide unfettered access through the top 25 of the body 24. Thus, the cover system 20 is provided with a ridge pole 40 that extends along the length of the body and is pivotably connected to each bow at a pivot connection 41, as shown in FIGS. 1-3. In the prior systems, the ridge pole 40 is generally located along the centerline of the dump body 24 and serves to hold the bows for movement in unison. A deployment cable 44 is provided that is used to pull the ridge pole 40, and thus all of the bows 31, from the deployed position of FIGS. 1-2 to the retracted position of FIG. 3.
The cover system 20 shown in FIGS. 1-3 is a known system, such as is disclosed in U.S. Pat. No. 5,487,584. One detriment of this system is that the bows 31, and the associated pivot mounts 34 and engaging elements 36, interfere with the open top 25 of the trailer or body 24. There is a need for a cover system that is suitable for heaped loads but avoids the problems of the prior devices.